Science > Physics > Re: Seated Chest Press vs Smith Machine Bench Press
| Topic: |
Science > Physics |
| User: |
"Prisoner at War" |
| Date: |
04 Feb 2008 12:23:02 PM |
| Object: |
Re: Seated Chest Press vs Smith Machine Bench Press |
On Feb 3, 12:48 pm, Bob Feduniak <robertfedun...@msn.com> wrote:
Thanks to all for your responses. Here's some added info in response
to questions in your responses:
I use a Tuff Stuff Apollo5 machine for seated chest presses. So I'm
sitting straight up and pressing horizontally at a 90 degree angle to
my chest. It seems like this should involve exactly the same muscles
as a prone bench press or prone Smith press (apart from not involving
supporting muscles with the machines). But it "feels" as though there
is much more strain on my arms with the traditional bench press or the
prone Smith machine bench press. By "heavy weights" I mean weights
for which 1 - 4 reps is difficult. For me, that's in the 200 lb area
on the bench. I don't know if the numbers on the weight stacks of
machines mean anything, It's the whole stack on the Apollo5.
Thanks again,
Bob F
It appears to be a simple matter of gravity and weight distribution.
There are similar machines at my gym, and they all push out that way.
I can do a whole heck of a lot more weight on them than I can do with
a free-weight barbell bench press, up to ninety pounds more! And
that's because pushing up, vertically, is inherently harder than
pushing away horizontally, especially when that horizontal push is
passively, indirectly helped by a support structure, such as you have
with a machine (remember, *all* machines make life easier).
I'm sure there's a Physics 101 principle and corresponding formula
involved, too, but to my mind -- and I'm not even mechanically
inclined -- it seems intuitively obvious why pushing weight against
gravity should be harder than pushing with a passive support structure.
.
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| User: "Rock Brentwood" |
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| Title: Re: Seated Chest Press vs Smith Machine Bench Press |
05 Feb 2008 12:06:14 AM |
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On Feb 4, 12:23=A0pm, Prisoner at War <prisoner_at_...@yahoo.com> wrote:
It appears to be a simple matter of gravity and weight distribution.
There are similar machines at my gym, and they all push out that way.
I can do a whole heck of a lot more weight on them than I can do with
a free-weight barbell bench press, up to ninety pounds more! =A0And
that's because pushing up, vertically, is inherently harder than
pushing away horizontally, especially when that horizontal push is
passively, indirectly helped by a support structure, such as you have
with a machine (remember, *all* machines make life easier).
No, that can't be it; because the same disparity is there even on
machines where the push is straight up and in every other way the same
as a bench press.
I thought early on that it might be psychological. But now I'm
beginning to realise that this may be nothing more than old wisdom:
the burdening brought on by the need for fine balance control plays a
significant part in the lifting. The machine may take that away if it
does not allow differential control for left and right. Even
differential control on a machine may not be enough to make up the
difference.
.
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| User: "spodosaurus" |
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| Title: Re: Seated Chest Press vs Smith Machine Bench Press |
04 Feb 2008 06:40:13 PM |
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Prisoner at War wrote:
On Feb 3, 12:48 pm, Bob Feduniak <robertfedun...@msn.com> wrote:
Thanks to all for your responses. Here's some added info in response
to questions in your responses:
I use a Tuff Stuff Apollo5 machine for seated chest presses. So I'm
sitting straight up and pressing horizontally at a 90 degree angle to
my chest. It seems like this should involve exactly the same muscles
as a prone bench press or prone Smith press (apart from not involving
supporting muscles with the machines). But it "feels" as though there
is much more strain on my arms with the traditional bench press or the
prone Smith machine bench press. By "heavy weights" I mean weights
for which 1 - 4 reps is difficult. For me, that's in the 200 lb area
on the bench. I don't know if the numbers on the weight stacks of
machines mean anything, It's the whole stack on the Apollo5.
Thanks again,
Bob F
It appears to be a simple matter of gravity and weight distribution.
There are similar machines at my gym, and they all push out that way.
I can do a whole heck of a lot more weight on them than I can do with
a free-weight barbell bench press, up to ninety pounds more! And
that's because pushing up, vertically, is inherently harder than
pushing away horizontally, especially when that horizontal push is
passively, indirectly helped by a support structure, such as you have
with a machine (remember, *all* machines make life easier).
Gravity doesn't go on leave when you're using a weight stack. Your
muscles don't know the difference between seated and prone. They
contract moving the humerus in the same plane relative to the body. The
difference is that there's not a 1:1 ratio of weight stack setting to
weight actually used and, more importantly, you're not doing a real
bench press. You do not have to stabilise the weight at all and you can
apply force vectors at all sorts of off angles and the machine isn't
going to allow the hands to move off at tangents.
I'm sure there's a Physics 101 principle and corresponding formula
involved, too, but to my mind -- and I'm not even mechanically
inclined -- it seems intuitively obvious why pushing weight against
gravity should be harder than pushing with a passive support structure.
Gravity doesn't go on leave when you're using a weight stack.
Your intuition needs a tune up. Or maybe just a replacement.
Ari
--
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